If you have a mobile with a smaller board where you're
expecting the SAS board, you might have the IMTS or RCC version... that's what
was used to make phone calls before cellular. The bad news is that these
boards do NOT have a squelch circuit. So, as far as I know, you can't
covert them to repeater use. The RF modules are fine. So
try to find a real SAS board, or use a third party squelch board.
One good thing, if you got this version, you likely go 10 pairs of channel ICOMS.
More than enough for your mods.

These are pictures of the IMTS 'SAS' board. Bad
news if you have this board.